Since the 3.1 patch I have had problems with Tw on my Ranger.
I use standard UI, no mods. On Alt hotbar slot 1 the TW works for a while then after a zoning it will stop working. I have tried removing then re-equiping but this does nto work. Tronkita has experience of this and suggested I remove the feat and the Icon then zone then re-equip and this works most of the time to get TW going again. If it does not work then I need to restart client and it re-equip and then it is working again.
When it stops workign the icon darkens momentarily so it is seeing the key-stroke but it fails to engage. This is extremely annoying and I have wiped a few instances when TW fails. It means I am very nervous about trying HM's and that I need to probably zone into them with TW removed and then add it each time in the playing instance. What a pain.
I have tried swapping slots but the problem persists. My ranger will only get FH in the next day or so so I will only then be able to see if FH is also affected.
My other toons have no problems with alt slot 1 and my barb has TW and FH and they seem fine.
I posted a comment about this in the general section but I think it probably better belongs here.
As I mentioned, Tronkita has experience of this problem. I also played with a Sin the other day who also had similar.
Before 3.1, my DT had a bugged slot 6 on the alt bar. On zoning slot 6 would always empty and I would have to re-equip it. Post 3.1 the problem has gone. The slot 6 problem had also been affecting other players I know. I use 2 pc's and the problem was consistent so I do not believe that it is due to local files.